Vagus nerve stimulation reduces daytime sleepiness in epilepsy patients. Malow BA, Edwards J, Marzec M, Sagher O, Ross D, Fromes G. Neurology. 2001 Sep 11;57(5):879-84
Transcutaneous vagus nerve stimulation for primary insomnia and affective disorder:a report of 35 cases]. Luo M, Qu X, Li S, Zhao J, Zhao Y, Jiao Y, Rong P. Zhongguo Zhen Jiu. 2017 Mar 12;37(3):269-273. doi: 10.13703/j.0255-2930.2017.03.013. Chinese